Anatomy of a canceled flight

My phone buzzed in the darkness of my Los Angeles hotel room a few weeks ago. It was American Airlines announcing that my flight due to take off in five hours was canceled due to bad weather.

It seemed reasonable. High winds and heavy snow were bearing down on Chicago, where I was headed. But then I checked American's website to find that eight other flights from LA to O'Hare International Airport were flying as planned, including departures two hours before my flight and three hours after.

American rebooked me on a flight for the next morning, but with all those other flights still operating, I called the airline to get a seat on one of them. All booked, I was told.

It seemed like yet another frustration from an ever less cuddly aviation industry. How could a storm clobbering Chicago affect just one flight out of nine and leave me no recourse for getting home on the day I had planned?

American Airlines spokeswoman Mary Frances Fagan said such decisions are made for two principle reasons: air safety and keeping the system on schedule as much as possible. Though the scenario might seem like a head scratcher to the inconvenienced traveler, a host of moving parts is at work, she said.

(Time magazine recently published a cover story on the subject called "Mission Impossible," and it's worth a read.)

The first stop for such decisions, Fagan said, is a computer algorithm affectionately called the Cancellator, which weighs weather reports to recommend which flights to cancel. The suggestions are reviewed by airline staffers who keep in frequent contact with local airports and the Federal Aviation Administration.

"Then we set into play a system of cancellations so that when we fly, we can fly the flights we say were going to operate," Fagan said.

According to American records, Fagan said, the airline could have flown all its scheduled flights into and out of O'Hare the day my flight was canceled. But hampered airport operations would have resulted in an average delay of 211 minutes per flight. Rather than saddle every inbound and outbound flight with such a holdup, she said, the airline cancels enough flights — that day it was about 40 percent of its O'Hare schedule — to operate the flights it chooses to run on time.

"In a market like LA, we may look at it and say, 'We have two planes leaving within two hours of each other" and cancel one to lessen the load on the hampered airport, Fagan said. Meanwhile, other flights — like long-haul and international routes —generally will rise to the top of the priority list.

So why was my flight the only one picked from the nine?

"A myriad of factors," Fagan said, which can include where the plane and crew need to be later in the day and the anticipated weather at the time of arrival. So essentially, I was unlucky.

Fortunately — and I credit American for this — I learned of my canceled flight far enough in advance that I simply ended up with an extra day in Los Angeles while it was 2 degrees back home. I'll take that unluckiness every time.

But had I absolutely needed to be back in Chicago as planned, the end of the story would have been a bit less rosy.